The present invention relates to a multicontact connector against interference, of the type comprising a conductive casing, a plurality of contacts housed in the said casing, and a plurality of clipping diodes each associated with a contact, each of the diodes being connected on the one hand to the corresponding contact and on the other hand to a metal layer forming an earth plane and connected electrically to the casing of the connector.
Electronic equipment on board aircraft require increasingly to be protected against interference which can impair their functioning, or even destroy them, with all the conceivable dramatic consequences.
Among this interference is found in particular the nuclear and luminous electromagnetic pulses generated by a nuclear explosion and lightning respectively, as well as electrostatic discharges.
This interference acts directly at equipment level, either by conduction at the level of the incoming and outgoing wiring of the equipment, or by induction.
A first step in the protection consists in housing the equipment in a metal environment, forming a Faraday cage, which protects it from part of the interference.
The problem arises at the level of the input/output connections of the equipment with the outside.
Indeed, the connectors are so many windows open to the outside and through which interference is liable to engender disturbances.
For the abovementioned interference, the disturbances appear in the form of transient discharges of voltage or of current, depending on whether the impedance of the line is high or low.
To eliminate such interference, it has been proposed to associate with the contacts of the connectors semiconductor diodes, in particular of Transil or Transzorb type, designed to clip overvoltages and dissipate large energies under transient conditions.
This involves avalanche diodes which possess very short response times and energy absorption capabilities such that they make it possible to do away with the majority of transients generated by interference related to lightning, to a nuclear explosion or of electrostatic origin.
Such diodes, which take a substantially cylindrical shape with two disc-shaped electrodes arranged on either side of a cylindrical active central part, are known.
Such diodes have relatively sizeable dimensions as compared with those of the contacts of the multicontact connectors, and owing to their dimensions have not hitherto been able to be implemented satisfactorily with connectors with a high density of contacts in which the separation between contacts can be less than the diameter of the diodes.